Study On Temperature Effect On Greep Of Axially Compressed Concrete Filled Steel Tubular Members

Creep is one of the most important impacts of long term behavior of concrete. It have been 20 years for carrying out researches of temperature effect on concrete creep, and temperature factor are attracting more attention as one of all factors about concrete creep. However, there is no work about temperature effect on creep of Concrete Filled Steel Tube (CFST).On the basis of the numerical differential method of temperature effect on concrete creep by micro-prestressed solidification theory model and using the experimental data of more than forty curves and calculated data of curves by B3 parameters, the paper calculate the weight number and regress the modify parameters of B3 model.By adopting the modified model, a new creep model is developed for temperature effect on axially compressed CFST members, which considers the micro-mechanism of creep and the characteristics of core concrete more reasonably. Comparising the calculate curve with experimental data under normal temperature. It shows the model is applicable to CFST members.On the basis of the above work, detailed parameter analysis is being carried out. The temperature effect on axially compressed CFST members is analyzed with constant and variable temperature. High and low temperature effects as well as the cyclic temperature and continuum rising temperature effects on axially compressed CFST members are studied. In addition, the paper analyzs the no-temperature effects on axially compressed CFST members, such as water cement ratio, aggregate cement ratio, steel ratio, stress ration, loading age and so on.